Influences of Changes in Salinity on Release of Carbon by Phytoplankton

1. Influences of Changes in Salinity on Release of Carbon by Phytoplankton Lab, Field, and Modeling Study Jessica Wagner Century High School OGI & OHSU Mentors: Tawnya Peterson Joe Needoba Karen Watanabe

2. CMOP Center for Coastal Margin Observation & Prediction • Field work • Modeling • In Situ Data • Lab Experiments Project Relevance Water Samples, Carbon Model, Salinity Experiments

3. Focus/Question Estuary • Where fresh water meets salt water • Has many changes in salinity over short • periods of time • Important for fish-creates a habitat • Biologically very productive Question: How does the change in salinity affect the growth rate of freshwater Diatoms?

4. CDOM Cast Data • CDOM • Colored dissolved • organic matter http://www.gcrio.org

5. Analysis of Variants (ANOVA) -3 x 10 14 12 10 8 Slopes 6 4 2 5 10 15 20 25 30 35 40 45 50 Growth Rate vs. Salinity Conclusion: Growth rates are significantly different on the salinity range Salinity (PSU)

6. Salinity affects growth What does this mean for the estuary and carbon cycling? Salinity experiments that can show effect of changes in salinity on carbohydrates are needed How do changes in salinity affect dissolved carbon release by phytoplankton?

7. Salinity Experiment -May FW-Control ½ filtered fw ½ none filtered fw SW-Shock ½ Filtered sw ½ none filtered fw

8. Salinity Experiment-July FW-Control ½ filtered fw ½ none filtered fw SW-Shock ½ Filtered sw ½ none filtered fw

9. Summary • Salinity affects growth of diatom • CDOM release increased as salt water was added to fresh water phytoplankton • However, No effect on July Salinity experiment • Different Seasons, Different Location in the river, Different species (Salt-tolerant) • Future Hypothesis/Testing • Different salt tolerance on other species of diatoms

10. Thank You -My Mentors Tawnya Peterson, Joe Needoba, and Karen Watanabe -K-12 Director Karen Wegner -CMOP -ASE